Given the Following Linear Programming Problem with Two Non-Negative Variables $\left(X_{1}\right.$

Given the following linear programming problem with two non-negative variables $\left(X_{1}\right.$ and $\left.X_{2}\right)$ , find the range of feasibility for the RHS and range of values for the objective function coefficients that will leave the current solution optimal. You may use graphical method for your analysis, since the problem has only 2 decision variables
Max: $50 X_{1}+75 X_{2}$
Constraints: $2 X_{1}+5 X_{2} \leq 99 \quad 5 X_{1}+4 X_{2} \leq 120$
Variables are non-negative